i'm terrell brown. this morning in afghanistan the taliban is claiming responsibility for a suicide attack that killed at least 14 people, including three nato service members. a suicide bomber riding a motorcycle rammed into a patrol. americans have a large presence there. nato is trying to sort out a weekend attack in afghanistan that left two americans dead. the casualties push the number of u.s. personnel killed in afghanistan to 2,000. the circumstances of saturday's violence remains unclear but a fire fight broke out at a checkpoint in eastern afghanistan. what nato hasn't determined so far was the gun battle a result of an insider attack or a deadly misunderstanding. drew levinson reports. >> reporter: this weekend marked the deadly milestone in afghanistan. 2,000 american soldiers killed since the war began nearly 11 years ago. it happened at a checkpoint in the eastern part of the country. one american soldier, an american contractor and three afghan soldiers were killed in a fire fight. >> the